1. Field of the Invention
The present invention relates to an apparatus that permits sketching of a reflected image at a position offset from the original.
2. Description of the Prior Art
Image shifting tracing devices have been disclosed in the prior art, but each of the devices in the prior art have deficiencies which make use difficult. U.S. Pat. No. 1,970,035 utilizes a glass pane that reflects sufficiently so that the image that is seen on the glass pane will be viewed as being on a sheet of paper that is shifted from the image, but it is also inverted from the orientation of the original of the image.
U.S. Pat. No. 3,324,574 shows a device that essentially provides an image on a sheet of paper that is used for silhouette forming. It utilizes a mirror in a housing that has a glass sheet in front of the mirror angled at a 45.degree.. A peep hole is used, which makes viewing the image difficult, and the image that is reflected onto the glass sheet will be seen as overlying the dark surface of the tracing sheet that is used for cutting out the silhouette. As stated, a peep hole is used, and the orientation is in a different plane than the horizontal surface which is desired for doing tracing.
U.S. Pat. No. 2,079,508 shows a structure that has a housing that is positioned above a sheet of paper, and a mirror reflects a generally vertical picture onto a transparent or semi-transparent plate of material, and by looking through a view finder at the top, the image will be reflected down onto the sheet of paper.
U.S. Pat. No. 3,227,043 also shows a glass plate and a mirror for providing an image that is shifted from one location to another, but the patent discloses a substantially different way of doing it than the present device.
While the above patents show the general idea of image shifting, the structures become either quite complex, or lose light intensity because of projecting through a glass initially, and then through the partial reflecting or partial transparent glass. Others need an eye piece because of the way they are set up. The existing devices require the user to peer through an eye piece to maintain a single or constant point of sight. If, in these devices, the eye pieces were not provided the image would shift, making tracing difficult.
With the present device, the image does not move if the head or the viewing location changes. The image stays constant no matter from which point, or line of sight, the viewer chooses. This eliminates the need for an eye piece and provides a wide field for viewing, making operation easy.
Other patents which show the general state of the art and are of general interest include the following:
U.S. Pat. No. 1,479,691; PA0 U.S. Pat. No. 1,971,119; PA0 U.S. Pat. No. 3,741,624; PA0 U.S. Pat. No. 3,749,472; and PA0 U.S. Pat. No. 4,226,029.